Keep Relay app open



I want to keep the relay app open so that I can hear what my son says the first time he says it instead of having to open the app and let him know I am now listening. I can do this by going in to settings - display and setting auto-lock to never. But I’d rather not do this every afternoon and then go turn it back on again after he gets home. Other apps I have keep the phone on while the app is open. Can’t we have this option - perhaps a setting for people who want it the other way?